Wavelength converted semiconductor light emitting device

Patent metadata

Field	Value
Publication number	US-2016163931-A1
Application number	US-201414903727-A
Country	US
Kind code	A1
Filing date	Jul 3, 2014
Priority date	Jul 8, 2013
Publication date	Jun 9, 2016
Grant date	—

Abstract

In embodiments of the invention, a light emitting device includes a semiconductor structure including a light emitting layer disposed between an n-type region and a p-type region. A first wavelength converting layer is disposed in a path of light emitted by the light emitting layer. The first wavelength converting layer may be a wavelength converting ceramic. A second wavelength converting layer is fused to the first wavelength converting layer. The second wavelength converting layer may be a wavelength converting material disposed in glass.

First claim

1 . A light emitting device comprising:
a semiconductor structure comprising a light emitting layer disposed between an n-type region and a p-type region; a first wavelength converting layer disposed in a path of light emitted by the light emitting layer, wherein the first wavelength converting layer comprises a wavelength converting ceramic; and a second wavelength converting layer fused to the first wavelength converting layer, wherein the second wavelength converting layer comprises a wavelength converting material disposed in glass, wherein the first wavelength converting layer is disposed between the second wavelength converting layer and the semiconductor structure.

2 . The light emitting device of claim 1 wherein the first wavelength converting layer emits red light and the second wavelength converting layer emits green light.

3 . (canceled)

4 . The light emitting device of claim 1 wherein the first wavelength converting layer and the second wavelength converting layer have angled sidewalls.

5 . The light emitting device of claim 1 wherein:
the first wavelength converting layer and the second wavelength converting layer form a wavelength converting member;
a first portion of the wavelength converting member has a substantially vertical sidewall; and
a second portion of the wavelength converting member has an angled sidewall.

6 . The light emitting device of claim 1 further comprising a reflective material, wherein the reflective material is disposed adjacent each of a sidewall of the first wavelength converting layer, a sidewall of the second wavelength converting layer, and a sidewall of the semiconductor structure.

7 . A method comprising:
forming a wavelength converting element, said forming comprising:
forming a first wavelength converting layer, wherein the first wavelength converting layer is a wavelength converting ceramic;
fusing a second wavelength converting layer to the first wavelength converting layer, wherein fusing a second wavelength converting layer to the first wavelength converting layer comprises:
mixing a wavelength converting material with glass;
rolling the mixture into a sheet;
cutting the sheet to fit the first wavelength converting layer; and
fusing the cut sheet to the first wavelength converting layer;
dicing the wavelength converting element into a plurality of platelets; and after said dicing, attaching a platelet to a semiconductor light emitting device.

8 . The method of claim 7 wherein forming a first wavelength converting layer comprises sintering a phosphor into a wafer.

9 . (canceled)

10 . The method of claim 7 wherein fusing the cut sheet comprises heating the cut sheet and the first wavelength converting layer to a temperature greater than a reflow temperature of the glass.

11 . A method comprising:
forming a wavelength converting element, said forming comprising:
forming a first wavelength converting layer, wherein the first wavelength converting layer is a wavelength converting ceramic;
fusing a second wavelength converting layer to the first wavelength converting layer, wherein fusing a second wavelength converting layer to the first wavelength converting layer comprises:
mixing a wavelength converting material with glass;
depositing the mixture on the first wavelength converting layer;
spreading the mixture to form a substantially uniform thickness layer;
dicing the wavelength converting element into a plurality of platelets; and after said dicing, attaching a platelet to a semiconductor light emitting device.

12 . The method of claim 7 further comprising thinning the first wavelength converting layer prior to fusing the second wavelength converting layer to the first wavelength converting layer.

13 . The method of claim 7 further comprising thinning the second wavelength converting layer after fusing the second wavelength converting layer to the first wavelength converting layer.

14 . The method of claim 7 further comprising:
attaching a plurality of semiconductor light emitting device to a mount;
attaching a platelet to each semiconductor light emitting device in the plurality;
disposing reflective material between neighboring semiconductor light emitting devices in the plurality.

15 . The method of claim 14 further comprising thinning the reflective material after disposing the reflective material between neighboring semiconductor light emitting devices.

16 . The method of claim 7 wherein dicing the wavelength converting element into a plurality of platelets comprises forming an angled sidewall on each platelet.

17 . The method of claim 7 wherein dicing the wavelength converting element into a plurality of platelets comprises:
forming on a first portion of each platelet a sidewall having a first angle relative to a top surface of the platelet; and
forming on a second portion of each platelet a sidewall having a second angle relative to a top surface of the platelet;
wherein the first angle is different from the second angle.

Assignees

• Koninkl Philips Nv

Inventors

• Schricker April Dawn
• Shchekin Oleg Borisovich
• Choi Han Ho
• Schmidt Peter Josef

Classifications

• H10W90/734

  between a chip and a stacked insulating package substrate, interposer or RDL · CPC title

• H10W90/724

  between a chip and a stacked insulating package substrate, interposer or RDL · CPC title

• H10W90/00

  Package configurations · CPC title

• H10W74/15

  on active surfaces of flip-chip devices, e.g. underfills · CPC title

• H10H20/856

  Reflecting means · CPC title